Electric generator



` 'May 26.19.25. y 'v J; w. IQRRANCE ET AL ELECTRIC GENERATOR f.lNvENToR` Patented May 26, 1925.

PATENT OFFICE.

UNITED STATES JAMES WALKER TORRANCE ANI) JOHN MCKINNON TOBRANCE, OFFAILSWORTH, ENGLAND.

ELECTRIC GENERATOR.

Application ledJune 13, 1921. Serial No. 477,163.

To all 'LU/2.0m t may concern.'

Be it known that we, JAMES WALKER ToaA nANon and JOHN MoKrNNoN ToanANon,both British subjects, residing both at Failsworth, Lancashire,England,have invented Certain new and useful Improvements in ElectricGenerators, ot' which the following is a specification.

This invention relates to electric generators suitable for the electriclighting ot' vehicles and other `purposes where a compact and lightweight electric generator' or dynamo is desired.

It has already been proposed to build up the field magnets of electricgenerators or electric motors from a. number of thin or sheet metalstampings or plates, each in two or more parts and of such a shape as inassembling to interlock or overlap at the joints. According to thepresent invention the field magnet system which is constructed of metalplates or stampings bolted together each in two or more parts whichinassembling overlap and break joint, also form the frame of thegenerator, although it may be surrounded by a` light casing, thestampings being constructed with holes'to receive studs for clamping thestampings rigidly together and also to bolt thereto the end platescarrying the armature bearings, brush gear, automatic electromagneticrelay and. terl'ninals.

This invention comprises an improved construction et the plates ttor atwo pole generator with a single lield coil, or a tour pole generatorthe plates being so shaped that the trame .members and the coil membersof the plates can be assembled separately,a coil wound on a Yformerplaced on the latter and then .fitted into position and secured to thetrame members, one plate overlapping the adjacent one at the joint andbreaking joint.

The invention will be tally described with reference to the accompanyingdrawings.

Fig. 1 is a longitudinal sectional elevation of a two pole generatorwith a single .field coil.

Fig. 2 is a transverse section on line l.-l.

Fig. 3 is a side elevation of one of the stan'ipings to form the lieldmagnets.

Fig. t is a transverse section of the same.

F ig. 5 is a side elevation of the other stamping to form the fieldmagnets.

Fig. 6 is a transverse section of the same.

Fig. 7 is a. side elevation of stamping for pole piece to tit thestamping shown in Figs. and t.

Fig. 8 is a transverse section of the same.

Fig. 9 is a side elevation of stamping 'for pole piece to lit thestamping shown in Figs and 6.

Fig. l0 is a transverse section of the same.

Fig. l1 is a perspective view showing the stamping forming the lieldmagnets assembled.

Fig. 12 is a perspective view showing the stamping forming the polepieces assembled.

The armature A of the generator and` vcommutator B are of ordinaryconstruction mounted on ball bearings in end plate castings C C,preferably of aluminium.

rllhe lield magnet system is built up of a number of stampings or platesD D, in the shape of a rectangular frame with coil members projectinginwardly and central ly therefrom laid side by side in layers and boltedor riveted together, each layer being in two parts ot such a shape thatone layer will interlock with and break joint with the adjacent layer togive an etiicient inagnetic contact. j n

As shown in the drawing for a two pole magnet the plates are made in twosets D D, a plate D oit the one set alternating with the plate D ot theother set. The plates D are each made with the coil member al Z2 in twoparts, the part Z being integral with and projecting inwardly andcentrally from the trame member D and the part Z2 separate therefrom tocomplete the coil member, and the plates D are each made with the coilmember d in one piece but Separate from the frame member D', a gap 033being formed therein to receive the end ot the coil member d which whenin place will project inwardly and centrally within the 'frame or polemember.

The coil members are preferably made enlarged at the ends d* (somewhatof T shape) to torm a` pole shoe adjacent to the armature A..

ltltl The lield coils F are of ordinary construction being wound upon aformer or mandril ot the desired shape.

In assembling the plates or frame members D D are placed togetheralternately and bolted in position through the holes e as shown in Fig.l1 and the coil members Z2 and d are similarly placed togetheralternately as shown in Fig. 1Q, and are firmly secured by rivets c. Alield coil wound on a former is placed upon the core members (Z2 d andthe tree ends ot the coil members a e pushed into position between theYtrame inenbers D D', the ends of the Ymembers d entering the gaps inthe plate D and the ends ot the members (Z2 abutting against the ends otthe members l. A bolt or rivet is passed through the holes e2 and e3 tosecure the members together. The whole is then assembled as shown inFig. l and secured by bolts E to the end plate cast,- ings C C. A.casing- H may be iitted over the plates between the end castings C C.

The stamping-s or plates are ot so'it iron or low carbon mild steel, butin order to retain suilicient residual magnetism in the magneticcircuit, a proportion of the stampinggs or plates employedV can be otsteel ot such a quality as to have a goed magnetic retentivity in orderto sell2 excite and genrate after standing.

A space may be provided at G 'for an `automatic cutout (not, shown)within the casing or a cutout or automatic switch to cut in and out asthe voltage rises and falls may be attached in any convenient positionit desired.

By this construction a specially lightA weight and compact electricgenerator can be produced, the field magnets beineT ot stampingsdesigned to allow sulticient iron for the required output, and in two ormore parts to permit ot coils wound on a 'former being placed inposition during assembly, and end plates C C carrying the armaturebearings, the whole being' tied together and braced by stay rods orbolts.

that we claim `as our invention and desire to protect by Letters Patentis In a. iield magnetv system for electric genw craters built up of anumber of plates or stampings the combination with a magnetic coil of aset of plates of approximately rectangular shape with holes in hecorners, a

second set ot' plates ot approximately rectangular shape with holes inthe corners and a gap formed along one edge, the second set of platesalternatingA with the first set, a depending member projecting' inwardsfrom each of the plates ot'the lirst set, a set ot 5 coil carryingplates, a second set ot coil carryingr plates alternating' with thefirst, means for clamping the two sets oi coil earryinrcgr platestogether, means tor clanuliinej the coil carrying plates to the trameplates. pole shoes formed on the ends et the coil carrying` plates, endplates and bolts passing through the end plates and the holes in theapproximate rectangular plates to clamp the latter to the end plates.

In testimony whereof we have hereunto set our hands in presence ot twosubscribingl witnesses.

JAMES VALKER TORBANCE.

JOHN MCKINNON TORRANCE.

Witnesses:

J. OwnnN OBRIEN, GEO. H. OBninN.

